Fox sightings in a city are related to certain land use classes and sociodemographics: results from a citizen science project

Modeling Tick Populations: An Ecological Test Case for Gradient Boosted Trees

General linear models have been the foundational statistical framework used to discover the ecological processes that explain the distribution and abundance of natural populations. Analyses of the rapidly expanding cache of environmental and ecological data, however, require advanced statistical methods to contend with complexities inherent to extremely large natural data sets. Modern machine learning frameworks such as gradient boosted trees efficiently identify complex ecological relationships in massive data sets, which are expected to result in accurate predictions of the distribution and abundance of organisms in nature. However, rigorous assessments of the theoretical advantages of these methodologies on natural data sets are rare. Here we compare the abilities of gradient boosted and linear models to identify environmental features that explain observed variations in the distribution and abundance of blacklegged tick (Ixodes scapularis) populations in a data set collected across New York State over a ten-year period. The gradient boosted and linear models use similar environmental features to explain tick demography, although the gradient boosted models found non-linear relationships and interactions that are difficult to anticipate and often impractical to identify with a linear modeling framework. Further, the gradient boosted models predicted the distribution and abundance of ticks in years and areas beyond the training data with much greater accuracy than their linear model counterparts. The flexible gradient boosting framework also permitted additional model types that provide practical advantages for tick surveillance and public health. The results highlight the potential of gradient boosted models to discover novel ecological phenomena affecting pathogen demography and as a powerful public health tool to mitigate disease risks.

The contribution of citizen science in the surveillance of wildlife and related arthropods

Environmental and anthropogenic factors may significantly affect the diffusion of wild animals, enhancing the interface of human–wildlife interactions and driving the spread of pathogens and vector-borne diseases between animals and humans. However, in the last decade, the involvement of citizens in scientific research (the so-called citizen science approach, henceforth abbreviated as CS) provided a network of large-scale and cost-effective surveillance programmes of wildlife populations and their related arthropod species. Therefore, this review aims to illustrate different methods and tools used in CS studies, by arguing the main advantages and considering the limitations of this approach. The CS approach has proven to be an effective method for establishing density and distribution of several wild animal species, in urban, peri-urban and rural environments, as well a source of information regarding vector–host associations between arthropods and wildlife. Extensive efforts are recommended to motivate citizens to be involved in scientific projects to improve both their and our knowledge of the ecology and diseases of wildlife. Following the One Health paradigm, collaborative and multidisciplinary models for the surveillance of wildlife and related arthropod species should be further developed by harnessing the potentiality of the CS approach.

Tracking the impacts of COVID-19 pandemic-related debris on wildlife using digital platforms

Since the start of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; COVID-19) pandemic in December 2019, there have been global surges of single-use plastic use. Due to the importance of personal protective equipment (PPE) and sanitation items in protecting against virus transmission and from testing, facemasks, respirators, disposable gloves and disposable wet wipes have become global staples in households and institutions. Widespread use and insufficient infrastructure, combined with improper waste management have resulted in an emerging category of litter. With widespread presence in the environment, such items pose a direct threat to wildlife as animals can interact with them in a series of ways. We examined the scope of COVID-19 pandemic-related debris, including PPE and sanitation items, on wildlife from April 2020 to December 2021. We document the geographic occurrence of incidents, debris types, and consequences of incidents that were obtained from social media searches, unpublished reports from colleagues, and reports available from the citizen science database "Birds and Debris". There were 114 unique sightings of wildlife interactions with pandemic-related debris (38 from 2020 and 76 from 2021). Within the context of this dataset, most incidents involved birds (83.3 %), while fewer affected mammals (10.5 %), invertebrates (3.5 %), fish (1.8 %), and sea turtles (0.9 %). Sightings originated in 23 countries, and consisted mostly of entanglements (42.1 %) and nest incorporations (40.4 %). We verified sightings by contacting the original observers and were able to identify replicated sightings and increase the resolution of the data collected compared with previously published results. Due to the complexities associated with global use and accessibility of digital platforms, we likely underestimate the number of animals harmed by debris. Overall, the global scope of this study demonstrates that online and social media platforms are a valuable way to collect biologically relevant citizen science data and track rapidly emerging environmental challenges.

Colonization of Warsaw by the red fox Vulpes vulpes in the years 1976-2019

The red fox is one of the most adaptable carnivores inhabiting cities. The aim of our study was to describe the process of Warsaw colonization by the red fox. We focused on: (1) the fox distribution in Warsaw on the basis of presence-absence data (2005-2012) over a grid of 1 × 1 km², (2) the process of settlement in 29 green areas (study periods 1976-1978, 2004-2012, and 2016-2019) in relation to habitat type, and (3) temporal and spatial patterns of the red fox incidents (1998-2015) reported by Warsaw citizens. We found out that: (1) the red fox penetrated the whole city (i.e. its presence was confirmed in all squares of the grid), (2) 21% of the green areas were colonized in 1976-1978 but 93% in 2016-2019. Forests and riparian habitats were occupied more frequently than parks and cemeteries in 1976-1978 with no difference in the further years; (3) the probability of the fox incidents increased over years, was higher in June-October, on working days, and around noon, and with the share of discontinuous urban fabric in the buffers around incident locations. Nevertheless, the incidents only partially reflect population abundance trends and activity patterns of the species, so should be treated cautiously.

Spatial Aspects of Gardens Drive Ranging in Urban Foxes (Vulpes vulpes): The Resource Dispersion Hypothesis Revisited

Red foxes are a well-established species of urban ecosystems in the UK and worldwide. Understanding the spatial ecology of foxes in urban landscapes is important for enhancement of urban biodiversity and effective disease management. The Resource Dispersion Hypothesis (RDH) holds that territory (home range) size is linked to distribution and richness of habitat patches such that aggregation of rich resources should be negatively associated with range size. Here, we tested the RDH on a sample of 20 red foxes (Vulpes vulpes) in the city of Brighton and Hove. We focused on residential garden areas, as foxes were associated with these in previous studies. We equipped 12 male and 8 female foxes with GPS collars recording at 15 min intervals during discrete seasons over four years. We regressed fox core area size against garden size, number of garden patches, and edge density within and between patches as extracted from GIS in a series of bivariate linear mixed models. We found that foxes used smaller core areas where gardens were large and well-connected and larger core areas where numerous, smaller gardens were fragmented by internal barriers (e.g., fences, walls) or bisected by other habitats such as managed grassland or built-up areas. Our findings confirm the RDH and help to inform future urban planning for wildlife.

Spatial distribution of sarcoptic mange (Sarcoptes scabiei) in urban foxes (Vulpes vulpes) in Great Britain as determined by citizen science

Urban areas may support high densities of wild carnivores, and pathogens can strongly influence carnivore populations. Red foxes (Vulpes vulpes) are hosts of sarcoptic mange (Sarcoptes scabiei), which infects numerous species, and transmission can be density dependent. In Great Britain, urban red foxes (Vulpes vulpes) have recently increased in population density and undergone range expansions. Here we investigate corresponding changes in urban fox mange prevalence. We predicted a higher prevalence closer to historic epi/enzootics and lower prevalence where urban features reduce fox density and movements, i.e. large areas of public green space, and fragmented habitat, as measured by road length and urban perimeter shape complexity. We visually assessed mange symptoms from georeferenced images of urban foxes submitted online by the public, thus surveying private land on a national scale. We measured the proportion of foxes apparently showing mange and used SATSCAN to identify spatial clusters of high infection risk. Landscape features were extracted from urban layers in GIS to determine associations. Although mange was widespread, we identified a single cluster of high prevalence (37.1%) in Northwest and Central England, which exceeded double mean prevalence overall (15.1%) and mirrors the northward expansion of urban fox distribution. Prevalence was positively correlated with perimeter shape complexity and negatively correlated with distance to the nearest city with mange, although the latter association was weak. Our findings show that citizen science can effectively monitor diseases with highly visible symptoms and suggest that fox movements are influential in explaining spatial patterns of prevalence.

Occurrence of canine and feline lungworms in Arion vulgaris in a park of Vienna: First report of autochthonous Angiostrongylus vasorum, Aelurostrongylus abstrusus and Troglostrongylus brevior in Austria

So far, neither the feline lungworms Aelurostrongylus abstrusus and Troglostrongylus brevior nor the canine lungworm Angiostrongylus vasorum was reported in wildlife or intermediate hosts from Austria. The slug Arion vulgaris represents an invasive species in Europe and serves as intermediate host for several lungworm species. This study aimed to analyse the occurrence of metastrongyloid lungworm larvae in slugs in Vienna, Austria. Therefore, 193 A. vulgaris were collected in the central Prater park in summer 2016. Specimens were artificially digested, analysed microscopically for lungworm larvae, and species were confirmed via PCR and sequencing. Out of 193, five slugs were positive to lungworms (2.6%), one for A. vasorum, two for A. abstrusus (genotypes A and B) and one for T. brevior, and one slug had a mixed infection of A. abstrusus and T. brevior larvae. The current study is the first evidence on the endemicity of these metastrongyloid lungworm species in Austria.